Telephone-exchange system



J. L. McQUARRIE. TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED AueJ. 1919.

1,406,668. Patented Feb. 14, 1922.

2 SHEETSSHEET 1.

//1 yen for: James A MS GHQ/l7? y W My J. L. McQUAHRlE.

TELEPHONE EXCHANGE SYSTEM.

APPLICATION FILED AUG.7,19I9- 1,406,668, Patented Feb. 14, 1922.

2 SHEETS-SHEET 2.

Sub; A Sub.

UNlTED STATES JAMES L. MCQUARRIE, OF NEW YORK, N. Y., ASSIGNOR TO WES PATENT orrice.

TERN ELECTRIC com.

PANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.

TELEPHONE-EXCHANGE SYSTEM.

Specification of Letters Patent.

Patented Feb. 14, 1922.

Application filed August 7, 1919. Serial No. 315,826.

To all whom it may concern Be it known that I, JAMES L. MCQUARRIE, a citizen of the United States, residing at New York in the county of New York, State of New York, have invented certain new and useful Improvements in Telephone-Exchange Systems, of which the following is a full, clear, concise, and exact description.

This invention relates to improvements in telephone exchange systems and has particular reference to a selector switch therefor.

In systems employing what is commonly known as the step-by-step numerical selector switch, it is customary to initially step the brushes of the switch in a group selecting or primary movement and then operate the same in their secondary movement to select a desired line in the selected group. These successive and distinct operations increase the time necessary in making connection between calling and called subscribers.

An object of the present invention is to diminish the time required for a switch to select a desired line by causing the brushes thereof to simultaneously perform the group and line selecting operations. To this end, improved mechanism is provided whereby two sets of impulses may be transmitted to the switch at the same time to operate separate electromagnetic means which step the brushes along a line which is the component of the co-ordinate movements produced by the two sets of impulses until the desired line is reached.

Another object is to retain the brushes out of engagement with the contacts of V terminal bank during the simultaneous group and line selecting operations, and then move the same to engage the contacts of the desired line upon the termination of said operations.

The inventive idea involved is capable of receiving a variety of expressions, one of which, for the purpose of illustrating the invention, is shown in the accompanying drawings; but it is to be expressly understood that said drawings are employed merely for the purpose of facilitating the description of the invention as a whole and not to define the limits thereof, reference being had to the appended claims for th1s purpose.

In the drawings, Fig. 1 is an elevatlonal view of a selector switch constructed in accordance with the invention; Fig. 2 is a section on the line 2 2 of Fig. 1; Fig. 3 is a fragmentary detailed view of the terminal bank and the switch brushes; Fig. 4 is a simllar view of the means for moving the brushes into and out of engagement with the contacts of the terminal bank; Fig. 5 is a diagrammatm view of the circuit arrangement foroperating the switch.

Referring more particularly to Figs. 1 to 4 inclusive, a preferred embodiment of the switch 1s shown as consisting of a base 10 having a terminal bank 11 mounted thereon. A brush-carrying shaft 12 is carried by a vertically movable rack 13 and is mounted to slide transversely thereof in bearings 14. A horizontally movable rack 15 is slidable on a guide rod 16, and one end has a bearing 17 for receiving a guide rod 18 carried by the brush shaft 12. A vertical stepping magnet 19 1s mounted upon the base 10 and operates, through the pawl 20, to step rack 13 upwardly in a manner well known in the art. Likewise, the horizontal stepping magnet 21 operates pawl 22 to step the horizontal rack 15 to the left, as shown in the drawing, against the tension of a spring 23 which returns said rack to normal whenthe same is released.

In accordance with the present invention, sets of impulses are simultaneously-transmitted to the vertical and horizontal stepping magnets 19 and 21 so as to give to the brushes of the switch a movement along a line which may be defined as the component or resultant of the movements imparted by the horizontal and vertical magnets. This movement is across the terminal bank 11 and may be said to be diagonal as distinguished from the up-and-around or around and up movements commonly employed in switches of this character. In instances Where the digits of a number are not the same, the movement of the brushes of the switch will initially be diagonal and then either horizontal or vertical, but the complete line traversed will nevertheless be the component of the movements produced by the sets of impulses. It is thus apparent that the switch may be made to perform its group and line selecting movements simultaneously, and thus materially reduce the time required in establishing a connection to a called line,

The brushes 24, 25 and 26 of the switch are normally maintained in spaced relation with respect to the terminal bank, but upon completion f both the tens and units sets of 1mpuls'es, a brush-tripping magnet 27 1s operated, in a manner to later appear, to move said brushes into engagement with the desired set of contacts on the terminal bank.

For the purpose of moving the brushes into.

and out of engagement with the terminal bank 11, use is preferably made of an armature of magnet 27 which engages the free end of a trip arm 28 keyed to the shaft 12 and held in engagement with said armature by a spring 29 coiled about said shaft. When the magnet 27 is energized and attracts its armature, spring 29 exerts a pressure upon arm'28 and causes'the shaft 12 to rotate in its bearings 14 and move the brushes 24, 25 and 26 into engagement with the terminal bank. Upon release of the magnet 27, the reverse operation takes place. Release magnet 30 isprovided for permitting the return of the switch to normal by withdrawing the holding pawls 31 and 32 from engagement with the teeth of their respective racks 13 and 15. Rack 13 will then return to its norand attract their armatures.

mal position by gravity, and rack 15 will be returned to normal position by the sprlng 23.

Referring now to. Fig. 5 in which the circuit arrangement is disclosed for operating the selector switch, it is believed that the invention will be fully understood from the following description of the operation in establishing a connection between a calllng and a called subscriber. When the subscriber at substation A removes his receiver, a line finder B, which may be of any well-known construction and which is only conventionally shown in the drawing, will be operated to connect the subscribers line with the selector switch C. A circuit is then closed for line relays 33 and 34 which extends from negative battery, winding of relay 33, brush 35 of line finder B, contact 36 and its associated spring, subscribers substation A, contact 37 and its associated spring, brush 38 of line finder B, and winding of relay 34 to positive battery. Relays 33 and 34 energize Slow-to-release relay 39 is then energized by a circuit which may be traced from grounded battery, winding of relay 39, front contact and outer armature of either of the relays 33 or 34 to ground. The subscriber at substation A may now set the dials 40 and 41 of the impulse sending, device in accordance with the digits of the desired number and after operating both dials the same may be simultaneously released by depressing the rod 42, which action operates contact spring 43 to place ground upon the conductors 44 and 45. Re-

lay 33 will now find ground over conductor 44' and relay 34 will find ground over conductor 45. Rotation of dials 40 and 41 toward their normal positions operate to interrupt the circuits for relays 33 and 34 at contacts 36 and 37 to cause the armaturesof said relays tovibrate in accordance with the sets of tens and units impulses, whereby the brushes of switch G will be stepped to postepping magnet 19 extending from grounded battery, winding of magnet 19, sideswitch wiper 48 in position 1, inner armature and back contactof relay 33, left armature and front contact of relay 39 to ground, relay 39 remaining energized during the stepping operations of the switch. Each retraction of the inner armature of relay 34- establishes a circuit for horizontal stepping magnet 21 extending from grounded battery, winding of magnet 21, side-switch wiper 49 in position 1, inner armature and back contact of relay 34, left armature and front contact of relay 39 to ground. Thus vertical and horizontal stepping magnets 19 and 21 are operated simultaneously, with the result that the brushes of the switch will simul-' taneously perform the group and line selecting operations, the motion of the brushes being along a line which is the component of the movements produced by the two sets of impulses. At the termination of both sets of impulses, relays 33 and 34 maintain their armatures attracted and thus break the circuit for escape magnet 46 at the outer armatures and back contacts of said relays 33 and 34. Magnet 46, after an interval of time, releases and moves the side-switch wipers of the switch into position 2. Return of dials 40 and 41 may be made to also move rod 42 back to normal in any Well-known manner (not shown).

Should the calling subscriber at any time during the transmission of impulses replace his receiver upon the 'switchhook, relays 33 and 34 will become deenergized at the termination of the sending of both sets of impulses, and a circuit will be established for the slow-to-release restoring magnet 50 extending from grounded battery, windin of said magnet, oif-nOrmal contact'50' which was closed upon the first step of the switch, back contact and right-hand armature of relay 39, which also becomes deenergized when relays 33 and 34 release, back contact and outer armature of either relay'33 or 34, to ground. Magnet 50 operates to return the side-switch wipers to normal positions,

winding-of said magnet, back contact and right armature of brush tripping magnet 27 either the horizontal or vertical off-normal contacts 52 or 53 which are closed upon the first step of the stepping magnets, front contact and armature of restorlng magnet 50, to ground. Release magnet 51 energizes and locks up over a circuit extending from grounded battery, winding of magnet 51, back contact and right armature of magnet 27, either of the off-normal contacts 52 or 53, front contact and armature of magnet 51, to ground. Release 51 then returns the brushes of the switch to normal position.

Assuming now that the calling subscriber has not replaced his receiver upon its switchhook, when the side-switch Wipers of the switch move into position 2, a circuit is closed for escape magnet 46 extending from grounded battery, winding of magnet 46, side-switch wiper 47 in position 2, left armature and back contact of magnet 27, to ground. A circuit is 'also established for magnet 27 extending from grounded battery, winding of magnet 27, side-switch wiper 54 in position 2, back contact and armature of magnet 50, to ground. However, magnet 27 is slow to operate and does not remove the ground from its left armature before the circuit for escape magnet 46 is closed. Operation of magnet 27 moves brushes 24, 25 and 26 into engagement with the contacts of the terminal bank 11 to which the called line is connected. Should this line be busy, a ground will be found upon the test terminal associated with brush 26 and a circuit immediately established for restoring magnet 50 extending from grounded battery, winding of said magnet, side-switch wiper 55 in position 2, and brush 26 to ground upon said test terminal. Magnet 50 will energize and operate to return the side-switch wipers to normal position and since said magnet is slow to release it will also close the previously described circuit for release magnet 51 which extends through the off-normal contacts 52 and 53, and the switch will thereby be returned to normal. If the called line is idle, brushtripping magnet 27 will remain energized, and after a sufficient interval of time has elapsed, escape magnet 46, which is slow to release, will deenergize and move the'sideswitch wipers of the switch into position 3, in which position tripping magnet 27 will continue to remain energized. Movement of side-switch wiper 55 in .position 3 will place ground upon the test terminal of the called line, whereb the same will test busy to any other switch. Movement of the side-switch wipers 56 and 57 into energize and cause the release of relay 39.'

The previously described circuit for restoring magnet 50 through the back contact and right armature of relay 39 is then established, and magnet 50 operates to restore side-switch Wipers to normal positions. Energization of magnet 50 also removes the ground from the energizing circuit of brush-tripping magnet 27, which then releases and moves the brushes 24, 25 and 26 out of engagement with the terminal bank. Release magnet 51 also energizes and locks up as previously described and operates to restore the brushes of the switch to .normal, whereupon said switch is again in position 1' or another operation.

What is claimed is:

1. In a telephone exchange system, a selectively operable switch, a terminal bank therefor, a stationary contact on said bank, movable contacts normally out of engagement with said bank, means for producing two sets of numerical impulses, two actuating means for said movable contacts, one responsive to one and the other to another set of impulses, means including said two actuating means for imparting a motion to said switch relative to the other set of contacts along a line which is the component of the movements produced by said two sets of impulses, and means operable at the termination of said motion to move the movable contacts into engagement with said stationary contact.

2. In a telephone exchange system, a selectively operable switch, a terminal bank having stationary contacts, movable contacts for said switch, means for moving the last named contacts diagonally across said terminal bank in spaced relation thereto in selecting desired stationary contacts, and means for moving said movable contacts into engagement with the selected stationary contacts at the termination of said diagonal movement.

3. In a telephone exchange system, a selectively operable switch, a terminal bank, movable contacts for said switch, means for operating said movable contacts in a group selecting movement, means for operating said movable contacts in line selecting movement, means for simultaneously operating the last two mentioned means whereby the resultant movement of said movable contacts will be diagonally across said terminal bank, means for maintaining said movable contacts out of engagement with said. bank during the group and line selecting movements, and means for moving said movable tively operable switch, a terminal bank having stationary contacts, movable contacts for said switch, electromagnetic means for selecting movement, means including vari-- operating said movable contacts in a group selecting movement, electromagnetic means for operating said movable comtacts in a line ably operable impulse sending devices for simultaneously operating the two electromagnetic means, means for maintaining said movable contacts out of engagement with the stationary contacts of said bank during the group and line selecting movements, and electromagnetic means for moving said movable contacts into engagement with the selected stationary contacts at the termination of the group and line selecting movements.

5. A selectively operable switch including a contact bank, a movable brush-carrying shaft, brushes carried thereby and normally in spaced relation to said contact bank, two means for supporting said shaft and guiding the same in its movements, means for simultaneously operating said two means to move said brushes diagonally across said contact bank, and means operable to move said brushes into engagement with said bank at the termination of said diagonal movement.

6. A selectively operable switch including a contact bank, a movable brush-carrying shaft, brushes carried thereby and normally in spaced relation to said contact bank, angularly disposed shaft-supporting elements operable tomove said brushes in group and line selecting movements, electromagnetic means for simultaneously operating said supporting elements whereby the resultant movement of said brushes will be diagonally across said contact bank, and means operable to move said brushes into engagement with said bank at the termination of said diagonal movement.

7. In a telephone exchange system, a selectively operable switch, a movable contact for said switch, stationary contacts for said switch corresponding to numerals of a certain digit, other stationary contacts for said switch corresponding to numerals of another digit, said movable contact being normally out of engagement with said stationary contacts, means for producing sets of impulses representing said digits, two actuating means for said movable contact, one responsive to one set and the other to the other set of impulses, means including said two actuating means and operable stationary contactsalong a line which is the component of the movements produced by said two sets of digital impulses, and means for thereupon engaging said movable contact with a stationary contact.

8. In a telephone exchange system, a plurality of subscribers lines, a lesser number of selectively operable switches serving said line's, two sets of contacts for each switch, means for producing two sets of numerical impulses, two actuating means for one set of contacts, one responsive to one and the other to another set of impulses, and means including said two actuating means for imparting a motion to said switch relative to the other set of contacts along a line which is the component of the move ments produced by said two sets of impulses.

9. In a telephone exchange system, a selectively operable switch, sets of contacts, means for producing sets of numerical impulses, two actuating means for one set of contacts, one responsive to one and the other to another set of impulses, means for transmitting saichsets of impulses simultaneously,

means including said two actuating means and operable during the transmission of said sets of impulses for imparting a motion to'said switch relative to another set of contacts along a line which is the component of the movements produced by said sets of impulses, and a single release magnet for restoring said switch to normal.

10. In a telephone exchange system, a selectively operable switch, a terminal bank having stationary contacts, movable contacts for said switch normally s aced from said stationary contacts, means or imparting a motion to said movable contacts relative to said stationary contacts which will initially be diagonally across the terminal bank and then horizontally across the same, and means for thereupon engaging said movable contacts with said stationary contacts. v

11. In a telephone exchange system, a selectively operable switch, a terminal bank having stationary contacts, movable contacts for said switch normally spaced from said stationary contacts, means for impart-- ing a motion to said movable contacts relative to said stationary contacts which will initially be diagonally across the terminal bank and then vertically across the sanie, and means for thereupon engaging said movable contacts with said stationary contacts. I

In witness whereof, I hereunto subscribe my name this 4th day of August A. D.,

during the actuation thereof for imparting a motion to said switch relative to said JAMES L. McQUARRIE; 

